The flag of Colombia was adopted on November 26, 1861. It is a horizontal tricolor of yellow, blue and red. The yellow stripe takes up the top half of the flag and the blue and red take up a quarter of the space each.
The horizontal stripes (from top to bottom) of yellow, blue and red tricolor have a ratio of 2:1:1. It—together with that of Ecuador, also derived from the flag of Gran Colombia—is different from most other tricolor flags, either vertical or horizontal, in having stripes which are not equal in size. (Venezuela, whose flag is also derived from the same source, opted for a more conventional tricolor with equal stripes).